Influenzal Infection Research Articles

Evaluation of droplet dispersion during non-invasive ventilation, oxygen therapy, nebuliser treatment and chest physiotherapy in clinical practice: implications for management of pandemic influenza and other airborne infections

Influenza viruses are thought to be spread by droplets, but the role of aerosol dissemination is unclear and has not been assessed by previous studies. Oxygen therapy, nebulised medication and ventilatory support are treatments used in clinical practice to treat influenzal infection are thought to generate droplets or aerosols. Evaluation of the characteristics of droplet/aerosol dispersion around delivery systems during non-invasive ventilation (NIV), oxygen therapy, nebuliser treatment and chest physiotherapy by measuring droplet size, geographical distribution of droplets, decay in droplets over time after the interventions were discontinued. Three groups were studied: (1) normal controls, (2) subjects with coryzal symptoms and (3) adult patients with chronic lung disease who were admitted to hospital with an infective exacerbation. Each group received oxygen therapy, NIV using a vented mask system and a modified circuit with non-vented mask and exhalation filter, and nebulised saline. The patient group had a period of standardised chest physiotherapy treatment. Droplet counts in mean diameter size ranges from 0.3 to > 10 µm were measured with an counter placed adjacent to the face and at a 1-m distance from the subject/patient, at the height of the nose/mouth of an average health-care worker. NIV using a vented mask produced droplets in the large size range (> 10 µm) in patients (p = 0.042) and coryzal subjects (p = 0.044) compared with baseline values, but not in normal controls (p = 0.379), but this increase in large droplets was not seen using the NIV circuit modification. Chest physiotherapy produced droplets predominantly of > 10 µm (p = 0.003), which, as with NIV droplet count in the patients, had fallen significantly by 1 m. Oxygen therapy did not increase droplet count in any size range. Nebulised saline delivered droplets in the small- and medium-size aerosol/droplet range, but did not increase large-size droplet count. NIV and chest physiotherapy are droplet (not aerosol)-generating procedures, producing droplets of > 10 µm in size. Due to their large mass, most fall out on to local surfaces within 1 m. The only device producing an aerosol was the nebuliser and the output profile is consistent with nebuliser characteristics rather than dissemination of large droplets from patients. These findings suggest that health-care workers providing NIV and chest physiotherapy, working within 1 m of an infected patient should have a higher level of respiratory protection, but that infection control measures designed to limit aerosol spread may have less relevance for these procedures. These results may have infection control implications for other airborne infections, such as severe acute respiratory syndrome and tuberculosis, as well as for pandemic influenza infection.

Einsatz von Klosterfrau® Melissengeist bei grippalen Infekten

ADMINISTRATION OF KLOSTERFRAU® MELISSENGEIST FOR THE COMMON COLDOn average adults get a cold 3 to 4 times per year. More and more people tend to treat them with traditionally approved “homespun remedies”. In a drug monitoring study the impact of Klosterfrau ® Melissengeist, a traditional phytopharmaceutical, was evaluated in patients suffering from a common cold. Most of the ingredients (such as essential oils of balm leaves, inula radix, angelica radix, or clove) are characterized by their antibacterial and antiviral action. Most of them are also traditionally used in different cultures for treatment of a common cold. On the average an influenzal infection persists at the least for 7 to 10 days. Treatment with Klosterfrau ® Melissengeist led to a significant reduction of the cold symptoms already after 4 days. After 5 days 21% of the patients had completely recovered. The tolerability was rated as being “very good” or “good” for 93 % of the patients by the physicians and by 96 % of the patients.

Clinical, encephalographic and immunological aspects of the intrauterine influenzal infection

International Journal of Gynecology & ObstetricsVolume 70, Issue S1 p. A41-A41 Viral infections in pregnanacy Clinical, encephalographic and immunological aspects of the intrauterine influenzal infection D. Siann, D. SiannSearch for more papers by this authorM. Devdnrinni, M. DevdnrinniSearch for more papers by this authorB. Knrsnntin, B. KnrsnntinSearch for more papers by this authorM. Kokhia, M. KokhiaSearch for more papers by this author D. Siann, D. SiannSearch for more papers by this authorM. Devdnrinni, M. DevdnrinniSearch for more papers by this authorB. Knrsnntin, B. KnrsnntinSearch for more papers by this authorM. Kokhia, M. KokhiaSearch for more papers by this author First published: 09 December 2003 https://doi.org/10.1016/S0020-7292(00)82100-1AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume70, IssueS12000Pages A41-A41 RelatedInformation

Serial magnetic resonance imaging in post-infectious focal encephalitis due to influenza virus

Two cases of a 13-year-old girl and a 14-year-old boy with postinfectious focal encephalitis due to influenza are reported. The clinical and magnetic resonance imaging (MRI) findings included: (1) partial motor seizures as the initial central nervous system manifestation, appearing more than 20 days after the influenzal infection, (2) no change in the level of consciousness although a boy demonstrated apraxia, and (3) high signal intensity lesions noticed with T2-weighted MRI located mainly in the cortex. The girl's lesion appeared to resolve within 10 days on MRI, while that of the boy (demonstrated in the thalamus on a third MRI) resolved within 1 week. However, a new lesion appeared in the cortex approximately 1 month later, that was visualized on a fourth MRI. Small gadolinium-enhanced lesions also were noticed during earlier stages in both patients. The pathogenesis of these MRI lesions is unknown, but the coexistence of small enhancing lesions, rapidly resolving lesions, and the elevated thrombin anti-thrombin III complexes, may indicate the presence of an angiopathy. Serial MRI examinations in patients with postinfectious encephalitis may lead to a better understanding of the pathogenesis of this disorder.

Ribavirin Aerosol in the Elderly

Ribavirin aerosol is effective in treating respiratory syncytial virus and influenzal infections in children and young adults. It has not been studied in elderly patients. We evaluated the safety of ribavirin aerosol in eight elderly volunteers at high risk for influenza. Their mean age was 64 years; seven subjects had chronic obstructive pulmonary disease (COPD). Subjects received ribavirin aerosol for two or six hours with six hours between treatments. Regimens were continued for 96 hours. The drug was well tolerated. Subjects receiving ribavirin for 2 hours demonstrated a significant decrease in their forced expiratory volume in one second, peak expiratory flow rate and flow over the middle 50 percent of the forced vital capacity. These changes were small and the subjects' symptoms remained stable. Subjects receiving ribavirin for 6 hours had no significant changes in pulmonary function. We conclude that ribavirin aerosol is safe in elderly patients with underlying COPD.

Dependence of the cocarcinogenic action of influenza virus on the character of influenzal infection

Dependence of the cocarcinogenic action of influenza virus on the character of influenzal infection

Examination for influenza IgA and IgM antibodies in pregnancies associated with fetal neural-tube defects.

Early antenatal serum specimens were collected from 25 women who subsequently gave birth to infants with anencephaly or spina bifida. Fluorescent-antibody test for influenza-specific IgA and IgM antibodies, although shown to be reliable for the detection of recent influenzal infection, failed to demonstrate such infection in any of these women. Early infection was detected in one of 50 control women who gave birth to a healthy infant. The results indicate that influenzal infection in pregnancy was not a major cause of neural-tubal defects in Oxford during 1972--76, if a cause at all.

Reinfection with influenza A (H3N2) virus in young children and their families.

The frequency and consequences of reinfection with influenza A virus were studied by longitudinal observation of families for a three-year period in which two epidemics of influenza A (H3N2) occurred. Seven children followed from birth were reinfected 10-25 months after their first infection. Two children were reinfected by the same H3N2 virus while the others were reinfected with a closely related variant. At least five of these reinfections were accompanied by respiratory illness. Reinfection illness was similar to that accompanying primary infection. For children in the second and third year of life during the 1978 epidemic, the rate of infection was the same for those who had been previously infected (seven of 12) as for those who had not been previously infected (22 of 40). Reinfection was detected in 26% of older siblings and 6% of parents. The occurrence of reinfection may have important implications for elucidation of the protective immune response and for development of prophylaxis for influenzal infections.

DETECTION OF ACUTE SERUM ANTIBODIES TO A/NEW JERSEY/76 INFLUENZA VIRUS AFTER REMOVAL OF IgG WITH COWAN I STAPHYLOCOCCUS AUREUS

Cowan I strain of Staphylococcus aureus contains a cell wall substance, protein A, which can absorb most of the IgG from human serum; IgM, IgA, and IgD remain practically unaffected. In the present study, acute sera from children who received killed A/New Jersey/76 influenza virus vaccine were absorbed with S. aureus (Cowan I). An aliquot of the serum was also absorbed with S. aureus (Wood), a strain which does not contain protein A. A third aliquot was left unabsorbed. Hemagglutination-inhibiting (HAI) antibodies to A/New Jersey/76 antigen were determined on the three serum aliquots in tandem. The unabsorbed sera and sera which were absorbed with S. aureus (Wood) had comparable HAI antibody titers. The sera of 11 of 14 children had an eight-fold or less decline in HAI antibody titer after absorption with S. aureus (Cowan I); the sera of two other children decreased sixteen-fold. Only one child's serum had no detectable HAI antibodies after the absorption procedure with S. aureus (Cowan I). In contrast, the latter absorption completely removed HAI antibodies from the sera of a control group who had long-standing antibodies to A/New Jersey/76 (or an antigenically similar virus). The acute sera of the vaccinees which still contained HAI antibodies after S. aureus (Cowan I) absorption suggests the presence of specific IgM and/or IgA antibodies. This relatively simple absorption procedure performed on a single serum may be useful for the detection of an acute influenzal infection.

Effect of influenza viral infection on the ingestion and killing of bacteria by alveolar macrophages.

In experimental animals, influenza prediposes the lung to superinfection by reducing the antibacterial efficiency of the alveolar macrophage system. Because such defects may represent abnormalities in ingestion or inactivation of inhaled bacteria, these subcomponents of phagocytosis were tested in mice infected 5 days previously with influenza A virus (NWS or WSN). The mice were exposed to aerosols of Staphylococcus epidermidis and then the rates of bacterial inactivation and percentages of intracellularly located staphylococci were measured. Rates of bacterial inactivation were determined for the left lung by pour-plate enumeration methods. The percentage of ingested bacteria was determined in the in situ perfused right lung by histologically determining the intra- or extracellular location of 100 or more staphylococci. Rates of inactivation of S. epidermidis at 4 hours after bacterial challenge were: control, 90.1 per cent; WSN, 73.0 per cent; NWS, 68.6 per cent, P less than 0.01. The percentage of intracellular staphylococci at 4 hours were: control, 90.9 per cent; WSN, 69.9 per cent; and NWS, 73.8 per cent, P less than 0.01. Microcolonies of proliferating staphylococci were also observed within macrophages of mice infected with each strain of influenza. These experiments demonstrated that in this experimental model, influenzal infection impairs the inactivation of inhaled bacteria by retarding the ingestion of bacteria and by allowing bacteria to proliferate within macrophages.

Chemoprophylaxis of respiratory infections.

Summary Chemoprophylaxis of certain respiratory infections has been described. The benefit and cost of chemoprophylaxis of tuberculosis have been compared and indications outlined. While some protection against influenzal infection by drugs of the adamantane group has been demonstrated, chemoprophylaxis against respiratory virus infections is as yet unavailable or impractical. In diseases associated with impaired bronchial clearance the influence of long term chemoprophylaxis on the natural history of the disorders becomes less certain. Morbidity in chronic bronchitis and bronchiectasis may be reduced. In cystic fibrosis, however, although the prognosis has been undoubtedly improved by chemoprophylaxis, the effects of long term treatment of infection in the later stages are uncertain.

Primary Meningococcal Pneumonia

Three cases of pneumonia caused by Neisseria meningitidis group Y are reported. From the results of these cases, the following conclusions were made. N. meningitidis probably can cause serious infection without preceding blood stream invasion. Primary meningococcal pneumonia is not rare; it has no distinctive clinical presentation; and it may not be recognized by routine expectorated sputum cultures. In addition, it may be associated with recent influenzal and adenoviral infections. Lastly, meningococci of the serogroup Y are capable of causing serious disease. Antimicrobial susceptibility studies showed that all three group Y isolates were sensitive to sulfadiazine and rifampin as well as to penicillin, ampicillin, erythromycin, and chloramphenicol.

Correlation between blood group factors and susceptibility to experimental influenzal infection in man.

Correlation between blood group factors and susceptibility to experimental influenzal infection in man.

Fatal Diffuse Influenzal Pneumonia: Premortem Diagnosis by Lung Biopsy

Primary viral pneumonia is an uncommon but serious complication of influenzal infection. Pathologic changes in the lungs due to the virus per se are commonly obsecured by secondary bacterial infection. An extensive disseminated influenzal pneumonia in a 40-year-old woman was associated with intractable hypoxemia despite intensive supportive care, including continuous positive pressure breathing, hypothermia and adrenal corticosteroids. Open lung biopsy early in the course of the disease showed pathologic changes attributable to “pure” virus pneumonia free from bacterial superinfection at that time. Death eventually occurred from secondary bacterial and fungal pneumonia demonstrated at autopsy.

The post-mortem diagnosis of influenzal infection by fluorescent IgG, IgA and IgM antibody studies on necropsy blood.

Necropsy blood from cases diagnosed as dying from influenza A was examined for specific antibody in the IgG, IgA and IgM fractions and a specific diagnosis of recent infection was made if either IgM or IgA antibody and low titres of IgG antibody were found. By these criteria a diagnostic rate of 77% was found in those cases from whom no virus was isolated. The use of infected cell monolayers grown on polytetrafluoroethylene-coated slides gave a simple method of carrying out these antibody assays, and the use of necropsy blood did not require any special methods of transport of specimens to the virus laboratory.

Subakute sklerosierende leukoencephalitis unter dem initialbild einer akuten epidemischen encephalitis (akute parkinsonistische encephalitis) mit ausgeprägter entwicklung von Maulbeerzellen und Russell-Körperchen

During a minor epidemic of influenzal infections with slight accompanying meningitic and encephalitic symptoms, a 23-year-old patient, after a 2- to 3-month initial stage, showed a rapidly evolving Parkinsonian syndrome with generalized myoclonia. With rising temperature, loss of consciousness, focal cramps and pareses and signs of decortication with akinetic mutism developed. The original clinical picture of “acute encephalitic Parkinsonism” had given rise to the false diagnosis of epidemic lethargic encephalitis (Von Economo's disease). The neuropathological findings showed subacute, sclerosing leukoencephalitis with only very discrete demyelinization as well as perivascular and diffuse interstitial lymphoplasmocellular infiltrations with morular-cells and Russell's bodies. These findings apparently correspond to a very specific stage of the disease characterized by special immunological defensive mechanisms. This could be related to the conspicuous transformation of the clinical symptoms with rise of temperature and an increasing protein, especially globulin, content of the cerebrospinal fluid. The assumption is suggested that the “delayed” appearance of electroencephalographic findings with the periodically-occurring complexes of sharp and slow waves typical of SSLE are connected with peculiarities in the clinical course of the disease.

A long-time study of the blood lipids of two students of atherosclerosis.

A study of serum cholesterol and lipoproteins covering periods of 28 years in a male physician and 17 years in a female research worker showed relative constancy for the cholesterol levels and greater variability for the lipoproteins. Cholesterol was reduced sharply and temporarily just after each influenzal infection. In the male, the level of cholesterol was slightly above 300 mg/100 ml for more than 13 years. An extremely low cholesterol and high carbohydrate diet proved unacceptable. A more liberal, relatively low-saturated fat, low-cholesterol, and high polyunsaturated fatty acid diet with about 30% of the calories from fat, maintained the cholesterol level between 230 and 270 mg and has been followed with relish for a number of years. A myocardial infarction occurred 27 years after the study began. Clofibrate since then has reduced the cholesterol level further. The female subject is in good health and maintains cholesterol levels slightly below 300 mg on a usual American diet. She is 10 years younger than the male. Her —S 40-70 lipoproteins have usually been well below the male subject's. Weight gain and lack of exercise seemed regularly to increase both levels. The data are presented because we believe them to be accurate; their interpretation is for the reader. We hope he must wait for some time for the outcome of the study.

Comparison of overt and inapparent influenzal infection in ferret.

Comparison of overt and inapparent influenzal infection in ferret.

Effect of esculamine on experimental influenzal infection

Effect of esculamine on experimental influenzal infection

Combined effects of influenza virus infection and treatment with urethane on the appearance of lung tumors in mice

Swiss mice were intranasally infected with influenza A2 virus and treated with urethan in order to detect whether the joint action of the two agents would enhance the development of lung tumors. The average number per mouse of the typical lesions induced by the two treatments together with their location, their histological and histochemical characteristics and the percentage of death in the different groups of animals were recorded. Results indicated that 51.7 % of the mice infected with influenza virus and treated with urethan had both bronchial dysplastic lesions due to influenza virus, and tumors induced by urethan. In this group the number of tumors was smaller than in the mice treated with the carcinogen only and no invasive pulmonary carcinomas were observed. The dysplastic lesions caused by influenza A2 virus as well as the lung adenomas induced by urethan maintained their typical histological and histochemical characteristics even when occurring in a close position. The failure of urethan to enhance the induction of lung tumors in mice exposed to influenzal infection might be ascribed to the different primary sites of response of the pulmonary tissue to the two agents, i.e. the bronchial epithelium for influenza virus and the alveolar epithelium for urethan.